The present invention relates generally to rotary bearings and, more particularly, to mountings or supports for such bearings on connecting rods.
It is difficult to economically produce oil and gas from low permeability reservoir rocks. Hydraulic fracturing, a technique that increases rock reservoir permeability, often increases recovery rates, however. During hydraulic fracturing, a fluid is pumped into the earth under high pressure where it enters a reservoir rock and fractures it. Proppants are carried in suspension by the fluid into the fractures. When the pressure is released, the fractures partially close on the proppants leaving channels for oil and gas to flow to recovery wells.
Specialized pumps are used to develop the pressures necessary to complete a hydraulic fracturing procedure or xe2x80x9cfrac job.xe2x80x9d These pumps are usually provided with bearings that couple a number of like connecting rods to a crankshaft. These bearings usually incorporate bronze sleeves that encircle the crankshaft and prevent binding during normal use. Improper design of these sleeves, however, can restrict the flow of lubricant to their bearing surfaces. If flow is fully impeded, the sleeves and the pump can be severely damaged. Damage may be caused by the sleeves seizing upon the crankshaft so that their exterior surfaces grind away in their housings and by galling where their bearing surfaces are worn away by direct contact with the crankshaft. In either case, the affected pump must be immediately shut down and the bearings repaired. Such an event can be exceedingly time consuming and costly for an oilfield operator.
In light of the problems associated with the known connecting rod bearings, it is a principal object of the invention to provide a new connecting rod bearing that enhances the flow of lubricant across its bearing surface so as to prevent galling and other forms of damage by friction. Use of the new connecting rod bearing, then, will: minimize the likelihood of pump breakdowns, prolong pump life, reduce costs, and optimize profits.
It is a further object of the present invention to provide a connecting rod bearing of the type described whose crankshaft-engaging sleeve cannot under normal operating conditions rotate relative to its housing. In other words, the outer surface of the sleeve cannot be caused to grind away against the housing so as to result in a premature bearing failure.
It is another object of the invention to provide a bearing of the type described that is: self-aligning, easy to assemble, and quick to install on a connecting rod. Both assembly and installation can be accomplished with few tools and by laborers with minimal training.
It is an object of the invention to provide improved elements and arrangements thereof in a connecting rod bearing for the purposes described which is lightweight in construction, inexpensive to manufacture, and fully dependable in use.
Briefly, the bearing in accordance with this invention achieves the intended objects by featuring a housing having an attaching portion with an alignment plug extending therefrom and a retaining portion bolted to the attaching portion so as to define a transverse passageway. The attaching and retaining portions are each provided with a pair of bores respectively located on opposite sides of the passageway. The bores may be brought into alignment with one another and partially intersect the passageway. A pair of alignment pins is positioned in the bores and project into the passageway. A sleeve is positioned within the passageway and has a pair of C-shaped parts the ends of which are provided with notches for receiving the pins. The C-shaped parts are also provided with beveled areas adjacent the notches that define liquid lubricant reservoirs extending across the sleeve. A channel connects the beveled areas of one of the C-shaped parts to provide fluid communication between the lubricant reservoirs.
The foregoing and other objects, features and advantages of the present invention will become readily apparent upon further review of the following detailed description of the preferred embodiment as illustrated in the accompanying drawings.